1. Field of the Invention
This invention relates to an apparatus and method of sharing resources in an integrated CPU environment, and more particularly, sharing of unused or underutilized storage components.
2. Background Information
With chip manufacturing process technology continuing to improve integration, forming of a complete microprocessor system on a single chip has become very attractive. In the past, microprocessor systems, as illustrated in FIG. 1, have been composed of several discrete chips including processor 110, memory controller 130, I/O controller 180, and various graphics specific chips, such as graphics chip 120. FIG. 2 shows the discrete components in FIG. 1 integrated into processing unit 210.
Integrated CPU's (Central Processing Unit) have various usage models. One usage model, for example, is that of a business user. A business user in this model may use the microprocessor core and two-dimensional (2D) portions of a graphics processor heavily, but may not utilize a three-dimensional (3D) portion of the graphics processor. Another usage model, for example, may be that of a computer enthusiast. The user in this model may wish to upgrade graphics capabilities of a computer system and install an external accelerated graphics port (AGP) graphics card. This user, as a consequence of installing the AGP graphics card, disables the graphics portion of integrated CPU 210. While these examples may be extremes, an average user may also not use all CPU resources at all times. For example, an average user that is “surfing” on the Internet will most likely not be using a 3D portion of the CPU heavily. Also, office productivity suites typically are CPU and memory intensive, but not very 3D graphics intensive. Furthermore, the graphics portion of integrated CPU's tend to be quite gate intensive. Therefore, typical graphics components have lots of memory structures and computational blocks available. Since not all of the memory structures are in use at all times, the memory structure's usage is not optimized.